But at noon, when Caesar had sent three legions and the whole cavalry to forage with the legate Gaius Trebonius, [the enemy] swooped down on the foragers suddenly from all directions; indeed, they did not hold back from the standards and the legions.

I’m not entirely sure I’ve understood the expression sic uti … non absisterent correctly. “So that” seems entirely the wrong relation for this sentence, and I’m not sure the replacement I have is much better; I’m sure not having a fully clear idea of the sense of absistere doesn’t help much either.